In wireless communication systems (e.g., cellular communication systems such as High Speed Packet Access (HSPA)), a wireless device's performance is often limited by the interference levels in the cell in which the wireless device is operating. Interference levels set a limit on the range of operation of the wireless device with respect to the transmitting network node (e.g., a base station, such as a NodeB or an eNodeB). The operation of the wireless device may further be impacted when the traffic load of the cell is high and the network node is unable to provide the desired performance to the wireless device (e.g., in terms of bit rate). Interference can be mitigated by wireless devices that have certain capabilities or features, such as interference suppression or cancellation (IS/IC). Load levels depend on the traffic conditions within the cell. Sometimes, in order to alleviate the traffic within a particular cell it may be desirable to offload one or more wireless devices from the highly loaded cell to a less loaded cell.
In current 3GPP specifications there are Radio Resource Control (RRC) Reporting events or Handover events to trigger the different handover procedures in the Radio Network Controller (RNC). For example, there may arise a situation in which a wireless device is served by one cell, while at the same time, being within the coverage range of another neighboring cell. Based on measurement report(s) requested by the network over RRC (which may be configured on either a periodic or event triggered basis), the network can trigger an active set update or change the wireless device serving cell. For example, in TS 25.331 Radio Resource Control (RRC); Protocol Specification, the following “intra-frequency measurement” events are listed:                A. A primary Common Pilot Channel (CPICH) enters the reporting range (add a cell to active set).        B. A primary CPICH leaves the reporting range (remove a cell from active set).        C. A non-active primary CPICH becomes better than an active primary CPICH (replace a cell).        D. Change of best cell.        
In addition, the following proposal can help measuring the link quality against a given threshold:                E. A Primary CPICH becomes better than an absolute threshold.        F. A Primary CPICH becomes worse than an absolute threshold.        G. A non-active E-DCH but active DCH primary CPICH becomes better than an active E-DCH primary CPICH.        
In addition, there are the following “inter-frequency measurement” events:                A. Change of best frequency.        B. The estimated quality of the currently used frequency is below a certain threshold and the estimated quality of a non-used frequency is above a certain threshold.        C. The estimated quality of a non-used frequency is above a certain threshold.        D. The estimated quality of the currently used frequency is below a certain threshold.        E. The estimated quality of a non-used frequency is below a certain threshold.        F. The estimated quality of the currently used frequency is above a certain threshold.        G. Change of best cell on a configured secondary downlink frequency.        
The problem with this set of events is that although it reflects the received power conditions, it overlooks another quantity that is important to the wireless device's performance, namely the channel quality information (CQI). CQI reflects the instantaneous changes in the downlink channel. During the 3GPP study documented on heterogeneous networks in TR 25.800 Study on UMTS Heterogeneous Networks, it was recognized that the extra interference margin provided by interference cancellation (IC) could lead to the possibility for the network to offload the IC-enabled wireless device from a macro cell to a lower power node (LPN) within the same cell.